Cleanup instance_update so it only takes a UUID.

You know when you try to do something simple like tweak
instance_update and instance_update_and_get_original and
it turns out to have all these knock on effects? Yeah,
that.

I still think this is a good idea though. I'd like to live
in a future where we don't have instance ids at all at the
DB API level. We need to do this to get there.

Change-Id: Ia51d06beaec068a8544642a6a4bf489247ff61a0

1 files changed, 7 insertions, 0 deletions

diff --git a/nova/api/ec2/ec2utils.py b/nova/api/ec2/ec2utils.py
index ceb695a5e..7ad2033ce 100644
--- a/nova/api/ec2/ec2utils.py
+++ b/nova/api/ec2/ec2utils.py
@@ -81,6 +81,13 @@ def ec2_id_to_id(ec2_id):
         raise exception.InvalidEc2Id(ec2_id=ec2_id)
 
 
+def ec2_id_to_uuid(context, ec2_id):
+    """Convert an ec2 ID into an instance UUID"""
+    instance_id = ec2_id_to_id(ec2_id)
+    instance = db.instance_get(context, instance_id)
+    return instance['uuid']
+
+
 def image_ec2_id(image_id, image_type='ami'):
     """Returns image ec2_id using id and three letter type."""
     template = image_type + '-%08x'